Learn from your mistakes and share them...

What use is an F-call? Recently I received an email from an Amateur who has had their license for over 30 years and been in the electronics field for more than 40. He shared with me an experience that goes to the heart of why it pays to share, even if this particular experience left his mates with sore bellies from laughing so hard. Without going into too much technical background, the devil is in the detail. Our amateur, was working on a project which required a particular part. He was a little short, so after a quick check of the specs, substituted for a part with similar performance. The parts were duly soldered onto the board - bit of a mammoth task, 1.5mm separation, 21 components in a double row next to each other. A little later, more parts were needed. At this time our friend discovered that there was a difference between the two parts, one was an NPN Darlington transistor, the other a PNP Darlington transistor. If you don't know what that means, think of it as two identical devices that work in reverse, not the same, but similar to installing a diode back to front. So, the next task was to remove all those diligently soldered parts - without destroying them - since they were needed elsewhere. The morale of this story is: "Act in haste, regret at leisure." In this case, a quick read of the specs was the cause of the incorrect substitution, which resulted in extra soldering, belly aches for his mates and embarrassment for our friend. How does this affect you? It doesn't. But next time you're building a project you might think twice about quickly substituting parts and protecting your friends from hurting themselves when they laugh too hard. The German language has a wonderful word for this: "Schadenfreude" - pleasure derived from the misfortune of others. You know you shouldn't laugh, but you can't help yourself. No matter how experienced, how senior, or how junior. We all make mistakes. Share them with your mates, so they can learn and tell the story a couple of times, so you can learn. Tip for young players, a BC517 is an NPN Darlington transistor and a BC516 is a PNP one. I'm Onno VK6FLAB.